About Question enthuware.ocajp.i.v7.2.1023 :

[ETS User]

I dont have the file ExceptionClassSummary, is there somewhere we can download it from?

[admin]

Hello,

Please go to Study View tree and expand "Study References", there you will see a node named ExceptionClassSummary. Double click on it and the file will be extracted out to your ETS Viewer installation directory.

HTH,
Paul.

[insider]

The following snippet causes a compilation error stating that initializer is not able to complete normally:

Code: Select all

static { throw new RuntimeException(); }

But this one goes fine (except the runtime error but it's not the point):

Code: Select all

static { if (true) throw new RuntimeException(); }

Why does the compiler allow the second one to pass?

[admin]

if(true) is a special case as explained at the bottom of this page.

As an example, the following statement results in a compile-time error:

while (false) { x=3; }
because the statement x=3; is not reachable; but the superficially similar case:

if (false) { x=3; }
does not result in a compile-time error. An optimizing compiler may realize that the statement x=3; will never be executed and may choose to omit the code for that statement from the generated class file, but the statement x=3; is not regarded as "unreachable" in the technical sense specified here.

The rationale for this differing treatment is to allow programmers to define "flag variables" such as:

static final boolean DEBUG = false;
and then write code such as:

if (DEBUG) { x=3; }
The idea is that it should be possible to change the value of DEBUG from false to true or from true to false and then compile the code correctly with no other changes to the program text.

HTH,
Paul.

[Zoryanat]

Hi
I cannot access ExceptionClassSummary: when I double click on it in Study View I get an error message in pop up window saying that "Unable to extract data due to exception: C:\windows\system32\ExceptionSummary.pdf (Access is denied).
I really need that fine - and this is second time I am posting the issue. Could you please help me out and send it to my email or smth?
My email is zoryanat@ie.ibm.com

Many thanks!
Rds
Zoryana

[admin]

Very sorry about that. I missed your post. YOu can download it from here: http://enthuware.com/downloads/Exceptio ... ummary.pdf

BTW, you are getting the error because it is not able to extract the file in that location (c:\windows\system32). Please run ETS Viewer from a non-system location such as c:\temp and it should work.

HTH,
Paul.

[Zoryanat]

Thank you very much, Paul, that seems to sort me out.
Have a good one,
--
Rds
Zoryana

[Kevin_C]

I have a question about the ExceptionInInitializerError in general. Will this Error always pop up when you throw an Exception in an initializer-block, or are there exceptions to this where it will throw the Exception declared instead of the ExceptionInInitializerError?

[admin]

Basically, if the code in a static initializer throws an exception, that exception is wrapped inside ExceptionInInitializerError and ExceptionInInitializerError is thrown.
You might want to read the details here: http://docs.oracle.com/javase/7/docs/ap ... Error.html

[Mushfiq Mammadov]

ExceptionClassSummaryPdf:
ArrayIndexOutOfBoundsException is subclass of RuntimeException, but ArrayIndexOutOfBoundsException extends IndexOutOfBoundsException directly, not RuntimeException.

[admin]

Actually the document is trying to separate the runtime and checked exceptions that is why it says RuntimeException. But you are right. It does not directly extend RuntimeException and the sentence is misleading.
Fixed.
thank you for your feedback!